No matter how old your children are, they are required to provide proof of US citizenship when travelling abroad. The United States Passport Agency recommends that you apply for a passport for your newly born child as soon as a birth certificate is issued. The initial passport application is the most complicated and birth certificates have a way of being difficult to locate when a passport is required. Once issued and in the government's system, passports are readily replaced if lost, and are easily renewed at ten-year intervals.
